About 400 species are of cosmopolitan distribution, being especially common in temperate regions.

Geranium dissectum L.

English Cranesbill, Cut-Leaved Cranesbill

Geranium maculatum L.

American Cranesbill, Alumroot, Storksbill, Wild Geranium

The dried and powdered root (Stuart 1979) or a fluid extract prepared therefrom (Wren 1975) may be used externally as a haemostat. The root has also been recommended as a treatment for haemorrhoids (Stuart 1979), presumably on account of its content of astringent tannins.

Pelargonium L'Hér.

Perhaps 250 species are native to tropical regions especially South Africa. Geraniums of florists belong to this genus. Some are fragrant especially when bruised.

Patch testing with the leaf of Pelargonium species can cause irritant reactions and reactions registered as allergic should be accepted with caution (Agrup 1969). Four of 52 patients tested showed a positive reaction (Hjorth 1968). The reports of dermatitis from species of this genus are lacking in sufficient detail to confirm an allergenic effect (Schwartz et al. 1957, McCord 1962, Anderson 1923, Kaalund-Jørgensen 1951, Freundenthal 1924, Imschenetzky 1928, Williams 1924, Becker & O'Brien 1959).

Pelargonium odoratissimum L'Hér.

(syn. Geranium odoratissimum L.)

Oil of Geranium is derived from this and allied species (Arctander 1960). The constituents include esters of geraniol, citronellol and linalool (Budavari 1996). The composition of the oil can vary according to the source (Algerian, French, Bourbon). Oil of Geranium has been reported to cause contact dermatitis and cheilitis (Klarmann 1958). Geraniol was reported to have sensitising properties by Keil (1947). Oil of Geranium - East Indian is derived from Andropogon, (fam. Gramineae).